Writing a cppcheck rule for detecting hexadecimal escape sequences

[orbitcowboy]

I am trying to write a cppcheck rule that detects hexadecimal escape sequences in C/C++ code.

Here is an example code (test.c):

const char *c = "\x41g";

I noticed that cppcheck already converts it into its correct character interpretation ("\x41g" is equal to "Ag"):

$ cppcheck --rule=".+" test.c 
Checking test.c...
[test.c:1]: (style) found ' const char * c ; c = "Ag" ;'

Is there any way to write a rule that checks the input file, before it is preprocessed by cppcheck?

Many thanks

Martin

[Daniel Marjamäki]

I have not tried it.. but you should be able to use the "raw" tokenlist in the rule. Then your rule is executed before all the Tokenizer simplifications.
This sounds like a useful rule so feel free to add it in the Cppcheck repo.
Good luck!